A Multiresolution Approach with Method-Informed Statistical Analysis for Quantifying Lymphatic Pumping Dynamics.

Despite significant strides in lymphatic system imaging, the timely diagnosis of lymphatic disorders remains elusive. One main cause for this is the absence of standardized, quantitative methods for real-time analysis of lymphatic contractility. Here, we address this unmet need by combining near-infrared lymphangiography imaging with an innovative analytical workflow. We combined data acquisition, signal processing, and statistical analysis to integrate traditional peak and-valley with advanced wavelet time-frequency analyses. Decision theory was used to evaluate the primary drivers of attributable variance in lymphangiography measurements to generate a strategy for optimizing the number of repeat measurements needed per subject to increase measurement reliability. This approach not only offers detailed insights into lymphatic pumping behaviors across species, sex and age, but also significantly boosts the reliability of these measurements by incorporating multiple regions of interest and evaluating the lymphatic system under various gravitational loads. By addressing the critical need for improved imaging and quantification methods, our study offers a new standard approach for the imaging and analysis of lymphatic function that can improve our understanding, diagnosis, and treatment of lymphatic diseases. The results highlight the importance of comprehensive data acquisition strategies to fully capture the dynamic behavior of the lymphatic system.

A Case Report of Tension Hydrothorax Incited by Bowel Perforation.

We report the case of a 34-year-old man who developed cardiac arrest due to tension hydrothorax from colonic perforation. Tension hydrothorax, an entity characterized by pleural effusion leading to mediastinal compression, has not been reported in association with intraabdominal inflammation. Our patient developed respiratory insufficiency after repair of colonic perforation, followed by respiratory failure and cardiac arrest. Transthoracic echocardiography provided rapid diagnosis during decompensation and prompted a lifesaving thoracostomy. Clinicians should consider tension hydrothorax as a rare cause of hemodynamic collapse, even in the absence of liver failure, and use bedside tools like transthoracic echocardiography to facilitate diagnosis and intervention.

Lymphatic muscle cells are unique cells that undergo aging induced changes.

Lymphatic muscle cells (LMCs) within the wall of collecting lymphatic vessels exhibit tonic and autonomous phasic contractions, which drive active lymph transport to maintain tissue-fluid homeostasis and support immune surveillance. Damage to LMCs disrupts lymphatic function and is related to various diseases. Despite their importance, knowledge of the transcriptional signatures in LMCs and how they relate to lymphatic function in normal and disease contexts is largely missing. We have generated a comprehensive transcriptional single-cell atlas-including LMCs-of collecting lymphatic vessels in mouse dermis at various ages. We identified genes that distinguish LMCs from other types of muscle cells, characterized the phenotypical and transcriptomic changes in LMCs in aged vessels, and uncovered a pro-inflammatory microenvironment that suppresses the contractile apparatus in advanced-aged LMCs. Our findings provide a valuable resource to accelerate future research for the identification of potential drug targets on LMCs to preserve lymphatic vessel function as well as supporting studies to identify genetic causes of primary lymphedema currently with unknown molecular explanation.

The Neuroma Startle Sign: A Surgical Indicator of Proximity to an Injured Nerve.

During operative intervention for the treatment of symptomatic neuromas, the authors have observed a hypersensitive "startle" response to stimulation in proximity to the painful nerve. This physiologic sign is an indicator of the specific anatomic localization of the painful stimulus, commonly a symptomatic neuroma, that appears to be reproducible. The aim of this article is to describe this "neuroma startle sign," posit the underlying mechanism for this observation, and propose how this phenomenon could be clinically harnessed for innovation and optimization in both surgery and anesthesia for more effective symptomatic neuroma localization.

Intraoperative Dexamethasone Decreases Infectious Complications After Pancreaticoduodenectomy and is Associated with Long-Term Survival in Pancreatic Cancer.

BACKGROUND: Dexamethasone is administered intraoperatively to prevent anesthesia-related nausea and vomiting and to reduce postoperative opioid administration. However, the adverse effects of corticosteroids on anastomotic healing and wound infection as well as oncologic outcomes remain unclear. We analyzed the effect of intraoperative dexamethasone administration on surgical outcomes after pancreaticoduodenectomy and on long-term survival in pancreatic cancer patients. METHODS: A total of 679 pancreaticoduodenectomies from a prospectively maintained database were analyzed. Surgical outcomes were compared between patients who received intraoperative dexamethasone and those who did not. Kaplan-Meier curves and Cox-regression survival analysis were performed in patients with pancreatic cancer. A propensity analysis was done to reduce the inherent bias of retrospective design. RESULTS: Patients who received dexamethasone (117, 17.2%) were younger and more likely to be female than those who did not (p = 0.001). Overall and 30-day major morbidity were similar among all resected patients, although there were fewer infectious complications in the dexamethasone group (18.8% vs. 28.5%, p = 0.032). In pancreatic cancer patients, dexamethasone was associated with significantly improved median overall survival (46 vs. 22 months, p = 0.017). This effect occurred independently of stage, pathologic characteristics, or adjuvant therapy, with adjusted hazard ratios, derived from pre-propensity and post-propensity analysis, of 0.67 (0.47-0.97) and 0.57 (0.37-0.87), respectively. CONCLUSIONS: A single intraoperative dose of dexamethasone did not increase morbidity after pancreaticoduodenectomy and, in fact, was associated with a decrease in infectious complications. The treatment was independently associated with improved overall survival in patients with pancreatic adenocarcinoma, an effect that cannot be explained and needs further validation in a prospective setting.

Epidural Anesthesia to Facilitate Organ Blood Flow During the First Penile Transplantation in the United States: A Case Report.

Regional anesthesia has been used to help create local sympathectomy and improve blood flow in plastic surgery procedures involving tissue grafts and flaps. However, anesthetic techniques that reduce systemic vascular resistance must be used with caution in patients with aortic stenosis (AS). Combined neuraxial and general anesthesia with careful titration of the local anesthetic dose can be a safe approach for patients with AS undergoing microvascular procedures. We present the anesthetic management of the first North American penile transplant, on an obese patient with moderate AS.

Prevention of respiratory complications of the surgical patient: actionable plan for continued process improvement.

PURPOSE OF REVIEW: Postoperative respiratory complications (PRCs) increase hospitalization time, 30-day mortality and costs by up to $35 000. These outcomes measures have gained prominence as bundled payments have become more common. RECENT FINDINGS: Results of recent quantitative effectiveness studies and clinical trials provide a framework that helps develop center-specific treatment guidelines, tailored to minimize the risk of PRCs. The implementation of those protocols should be guided by a local, respected, and visible facilitator who leads proper implementation while inviting center-specific input from surgeons, anesthesiologists, and other perioperative stakeholders. SUMMARY: Preoperatively, patients should be risk-stratified for PRCs to individualize intraoperative choices and postoperative pathways. Laparoscopic compared with open surgery improves respiratory outcomes. High-risk patients should be treated by experienced providers based on locally developed bundle-interventions to optimize intraoperative treatment and ICU bed utilization. Intraoperatively, lung-protective ventilation (procedure-specific positive end-expiratory pressure utilization, and low driving pressure) and moderately restrictive fluid therapy should be used. To achieve surgical relaxation, high-dose neuromuscular blocking agents (and reversal agents) as well as high-dose opioids should be avoided; inhaled anesthetics improve surgical conditions while protecting the lungs. Patients should be extubated in reverse Trendelenburg position. Postoperatively, continuous positive airway pressure helps prevent airway collapse and protocolized, early mobilization improves cognitive and respiratory function.

Dose-Dependent Protective Effect of Inhalational Anesthetics Against Postoperative Respiratory Complications: A Prospective Analysis of Data on File From Three Hospitals in New England.

OBJECTIVES: Inhalational anesthetics are bronchodilators with immunomodulatory effects. We sought to determine the effect of inhalational anesthetic dose on risk of severe postoperative respiratory complications. DESIGN: Prospective analysis of data on file in surgical cases between January 2007 and December 2015. SETTING: Massachusetts General Hospital (tertiary referral center) and two affiliated community hospitals. PATIENTS: A total of 124,497 adult patients (105,267 in the study cohort and 19,230 in the validation cohort) undergoing noncardiac surgical procedures and requiring general anesthesia with endotracheal intubation. INTERVENTIONS: Median effective dose equivalent of inhalational anesthetics during surgery (derived from mean end-tidal inhalational anesthetic concentrations). MEASUREMENTS AND MAIN RESULTS: Postoperative respiratory complications occurred in 6,979 of 124,497 cases (5.61%). High inhalational anesthetic dose of 1.20 (1.13-1.30) (median [interquartile range])-fold median effective dose equivalent versus 0.57 (0.45-0.64)-fold median effective dose equivalent was associated with lower odds of postoperative respiratory complications (odds ratio, 0.59; 95% CI, 0.53-0.65; p < 0.001). Additionally, high inhalational anesthetic dose was associated with lower 30-day mortality and lower cost. Inhalational anesthetic dose increase and reduced risk of postoperative respiratory complications remained significant in sensitivity analyses stratified by preoperative and intraoperative risk factors. CONCLUSIONS: Intraoperative use of higher inhalational anesthetic doses is strongly associated with lower odds of postoperative respiratory complications, lower 30-day mortality, and lower cost of hospital care. The authors speculate based on these data that sedation with inhalational anesthetics outside of the operating room may likewise have protective effects that decrease the risk of respiratory complications in vulnerable patients.

IKs channels open slowly because KCNE1 accessory subunits slow the movement of S4 voltage sensors in KCNQ1 pore-forming subunits.

Human I(Ks) channels activate slowly with the onset of cardiac action potentials to repolarize the myocardium. I(Ks) channels are composed of KCNQ1 (Q1) pore-forming subunits that carry S4 voltage-sensor segments and KCNE1 (E1) accessory subunits. Together, Q1 and E1 subunits recapitulate the conductive and kinetic properties of I(Ks). How E1 modulates Q1 has been unclear. Investigators have variously posited that E1 slows the movement of S4 segments, slows opening and closing of the conduction pore, or modifies both aspects of electromechanical coupling. Here, we show that Q1 gating current can be resolved in the absence of E1, but not in its presence, consistent with slowed movement of the voltage sensor. E1 was directly demonstrated to slow S4 movement with a fluorescent probe on the Q1 voltage sensor. Direct correlation of the kinetics of S4 motion and ionic current indicated that slowing of sensor movement by E1 was both necessary and sufficient to determine the slow-activation time course of I(Ks).